package com.hmdp.utils;

import org.springframework.core.io.ClassPathResource;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.data.redis.core.script.DefaultRedisScript;
import org.springframework.data.redis.core.script.RedisScript;

import java.util.Collection;
import java.util.Collections;
import java.util.UUID;
import java.util.concurrent.TimeUnit;

public class SimpleRedisLock implements ILock{

    private static final String LOCK_PREFIX = "lock:";
    private static final String ID_PREFIX = UUID.randomUUID().toString()+"-";
    private static final DefaultRedisScript<Long> UNLOCK_SCRIPT;
    static {
        UNLOCK_SCRIPT = new DefaultRedisScript<>();
        UNLOCK_SCRIPT.setLocation(new ClassPathResource("unlock.lua"));
        UNLOCK_SCRIPT.setResultType(Long.class);
    }

    private StringRedisTemplate stringRedisTemplate;
    private String name;
    public SimpleRedisLock(String name,StringRedisTemplate stringRedisTemplate) {
        this.name = name;
        this.stringRedisTemplate = stringRedisTemplate;
    }


    @Override
    public boolean tryLock(long timeoutSec) {
        //获取线程的标识
        long threadId = Thread.currentThread().getId();
        String key = LOCK_PREFIX + name;
        String id = ID_PREFIX + threadId;
        //获取锁
        Boolean success = stringRedisTemplate.opsForValue().setIfAbsent(key, id, timeoutSec, TimeUnit.SECONDS);
        return Boolean.TRUE.equals(success);
    }

    @Override
    public void unLock() {
        stringRedisTemplate.execute(
                UNLOCK_SCRIPT,
                Collections.singletonList(LOCK_PREFIX + name),
                ID_PREFIX + Thread.currentThread().getId()
                );
//        //获取线程标识
//        String threadId = ID_PREFIX + Thread.currentThread().getId();
//        //判断标识是否一致
//        String id = stringRedisTemplate.opsForValue().get(LOCK_PREFIX + name);
//        //判断是否一致
//        if(threadId.equals(id)){
//            //释放锁
//            stringRedisTemplate.delete(LOCK_PREFIX + name);
//        }

    }
}
